WASHINGTON (CNN) -- An investment executive who paid more than $20 million for an original, handwritten copy of the Magna Carta presented the ancient paper Monday to the media and plans to loan it to the National Archives.

People photograph the rare copy of the Magna Carta before it's auctioned at Sotheby's New York in December.

David Rubenstein, the founder of the private equity company Carlyle Group, was the top bidder during a December auction at Sotheby's, and said buying it and displaying it is a way "to show my appreciation for the country which has been very good to me."

The National Archives considers the manuscript "a milestone in constitutional thought" from the 13th century, and plans to place it on public display later this month.

Rubenstein in the 1970s was the chief lawyer for a Senate panel that reviewed constitutional amendments.

The original Magna Carta was signed in 1215. Rubenstein's is one of four remaining copies of the document commissioned by the King of England in 1297 to establish basic human rights as part of English law.

Rubenstein, before founding the Washington-based Carlyle Group, was also a domestic policy adviser during the Carter administration. He is from Baltimore, Maryland.

The fragile paper is displayed in a sealed viewing box to protect it from damage. Sotheby's auctioned the document on behalf of the Ross Perot Foundation, which had purchased it in the 1980s from a British family who had kept the document for the previous 500 years.

"It has a few wrinkles," Rubenstein told reporters. "Any of you who are 700 years old, you'd have a few wrinkles as well, but for something that's as old as it is, it's in very good shape, and I know that it will be kept in excellent shape, hopefully for another 700 years."

The Magna Carta will be on public display starting March 12 in the West Rotunda Gallery of the National Archives Building.E-mail to a friend